The determination of likelihood of heart attacks or, more technically, coronary atherosclerosis, has been of vital concern not only to the medical profession but to the population in general. The news media abound with accounts of a person dying from a "heart attack," yet it was reported that person had just had a complete physical check-up and been pronounced fit.
Diastolic and systolic blood pressure has been the typical indicator used to diagnose a person's proneness to clinical coronary atherosclerosis for many years, yet this indicator is far from being infallible and a better indicator is desired.
The prior art has attempted to detect the existence of coronary artery disease or to determine the incidence and prevalence of coronary heart disease by many different methods and analyses. These include trying to determine the relationship of coronary risk to: occupational stress, education, sexual activity, annual income, behavior patterns, and socioeconomic background and status.
Motor retardation, that is, slowness of movement and speech, has been studied as an indicator of depressive illness. The hesitation pause times in the subject's speech has been observed to be significantly elongated while the patient was mentally depressed.
The voice fluency monitor is a new method of electronic monitoring of non-lexical conversational style, i.e., hesitation pauses. A hesitation pause is defined in an interview dialogue as joint silence bounced by the speech of the subject. The working hypotheses in the present invention are that hesitation pauses reflect behavioral maladaptation and are related predictively to the existence of coronary artery disease or to the development of coronary artery disease. The relevance of this synthesis of psycholinguistics and cardiovascular research is portrayed by recent evidence supporting psychologic and social risk factors for coronary disease. Standard risk factors, such as blood pressure, overweight, serum cholesterol, taken together, provide an incomplete estimate of the coronary disease burden of the population and an insensitive prediction of the risks of individuals. The need for simultaneous study of psychosocial and standard risk factors has been emphasized in order to shed light on pathophysiological mechanisms, and possibly provide insight for more effective disease programs. It is noted that several studies have already adhered to this design and in all of them it was found that the behavioral risk factor made an independent contribution to coronary risk after the influences of the standard biologic risk factors available for study were accounted for statistically.
Four separate studies have demonstrated a correlation of position in the socioeconomic hierarchy to coronary risk factors, morbidity, and mortality. In Cleveland, Ohio attorneys, coronary morbidity and mortality correlated to socioeconomic background and status. The coronary prevalence rate of the top socioeconomic group was significantly less than that of the middle group but not significantly less than that of the lowest group. These attorneys exhibited a similar profile in terms of family history of diabetes mellitus in one or both parents and in the three-year follow-up of coronary mortality.
The same pattern prevailed in a broader sample of an employed population in the Bell system ranging from executives to workmen. The greatest difference was between executives and foremen, the workmen being intermediate. Similar data were found in the DuPont Company hierarchy stratified into five economic groups, with Group I being the highest income group, and Group V the lowest income group. Groups I and II exhibited the lowest rates of myocardial infarction, diabetes mellitus, and hypertension, Group III the highest, and Groups IV and V intermediate.
Cleveland businessmen were stratified into three groups according to annual income. The top income group I was significantly different from the middle income group II, but not significantly different from the bottom income group III in exhibiting lower resting diastolic blood pressure, greater self esteem as measured on The Minnesota Multiphasic Personality Inventory, more well-controlled aggression on an Inkblot Test, and more vigor (Type A Style) in response to the R. Rosenman-M. Friedman Structured Tape Recorded Interview designed to elicit Type A.
Compatible findings were obtained in a study of sexual activity and coronary risk. Long-standing maladaptation was hypothesized in recently coronary-stricken subjects compared with normal coronary-prone subjects. Coronary risk correlated with less outwardly directed activity as a defense against underlying passive dependency, more influence of the latter on a decline of sexual activity over 25 years of marriage, less annual income and fewer children. Greater unresolved dependency needs also were described in patients with arteriosclerotic heart disease compared with valvular rheumatic heart disease patients.
Accordingly, an object of the invention is to provide a solution to the problem of detecting the existence of coronary artery disease or of better diagnosis of proneness to clinical coronary artery disease in human subjects.